(Reuters) - Two-time grand slam winner Victoria Azarenka said on Monday she has withdrawn from the U.S. Open as she is unwilling to part with her son during legal proceedings to separate from her former partner.

The 28-year-old Belarusian returned to action in June, after the birth of her son Leo last December, and had been hopeful that legal arrangements could be worked out to allow her to compete in the Aug. 28-Sept. 10 grand slam in New York.

"I am sadly unable to compete in this year's U.S. Open due to my ongoing family situation that I am working through," Azarenka said in a statement.

"While I will dearly miss being in New York and playing in one of my favourite tournaments where I have enjoyed some of the best moments in my career, I am already looking forward to being back next year."